Ingredients

   
113g unsalted butter (1 stick), softened
45g powdered sugar
1.5g salt
20g milk
150g AP flour
54g cornstarch
12g matcha powder

Steps

  1. Beat softened butter with powdered sugar and salt until smooth and combined.

  2. Add milk in two or three additions, mixing well after each.

  3. Sift the AP flour, cornstarch, and matcha together. Mix into the butter until it comes together into a dough. Do not overwork.

  4. Wrap the dough in plastic and roll into a sheet about 18×15cm, roughly 1cm thick. Chill 3 hours.

  5. Cut into batons about 1.5×6cm. Space on a parchment-lined sheet.

  6. Bake at 266°F for 45–50 minutes until set but not colored. Cool completely before serving — they firm up as they cool.

Analysis

Total batter weight: 396g

Component Amount %
Structure solids (flour + cornstarch) 204g 51.5%
Fat (butter) 93g 23.5%
Sugar (powdered) 46g 11.6%
Liquid (milk + butter water) 36g 9.1%
Egg/protein — —

Shortbread runs far higher structure and lower liquid than a drop cookie (which sits around 30–40% structure with an egg) — there’s no egg and no leavening, so the flour-and-cornstarch dominate and the dough holds its shape instead of spreading. That’s exactly what makes it sandy and tender. The 12g matcha (~3%) is an inert solid: it colors and flavors but doesn’t set.

Notes

  • A tender, sandy matcha shortbread. The low bake temperature keeps the green color bright — high heat dulls matcha to khaki.
  • This is a shortbread, not a creamed drop cookie, so it holds its shape and does not spread. The cornstarch and lack of leavening make it sandy and tender rather than chewy.
  • The high cornstarch replaces cake flour — cake flour is just AP cut with cornstarch (~86/14). The 150g AP + 54g cornstarch here gives the same low-protein, tender result without needing a special flour.
  • Powdered sugar is best: it dissolves fully into the butter for a fine, melt-in-the-mouth crumb, and the cornstarch in it adds tenderness. Granulated works in a pinch but bakes slightly crunchier with a touch more spread.
  • Use ceremonial or culinary-grade matcha you’d actually drink. Cheap matcha bakes bitter and brown.
  • Want them thicker? Roll the sheet to 1.5cm instead of 1cm and add 5–8 minutes to the bake. Because there’s no leavening, the baked thickness equals the rolled thickness — they won’t puff or spread, so roll to whatever height you want.
  • For a flavor swap, replace the 12g matcha with 12g hojicha powder, or 10g cocoa, or 8g instant espresso.
  • Dough can be rolled, wrapped, and frozen up to a month. Slice from frozen, add a few minutes to the bake.
  • Store in an airtight tin up to a week. They keep well — the low moisture content makes them shelf-stable.